Diary - Rachel Stirling

The tension in the wings causes a cast member to fart. I get the giggles, and the tape holding my mo

It's 7pm in the great grey Stalin of a building that is the National Theatre. The dressing rooms all face on to a central courtyard and, as has become tradition, the cast of the Henry IV plays gives us a good-luck "banging". We've had birthday bangings, preview bangings, congratulatory bangings. These involve actors leaning out of their windows and cheering while pounding on the panes of glass. In full medieval costume, they are a funny sight: putty warts, greasy grey wigs,

fat-suits and facial boils. An outsider might easily mistake them for the inmates of an asylum in revolt. Michael Gambon, whose window is opposite my own, is by far the naughtiest - the Jack Nicholson of our Cuckoo's Nest.

Then the dreaded announcement: "Ladies and gentlemen of the Theatre of Blood company, this is your act one beginners' call." A few minutes' grace, thank God, as press night never goes up on time. Which is just as well, because I have false eyelashes dangling dolefully from one of my lids, and I can't see to stick them back on.

Our play is a revamp of the 1973 film starring Vincent Price as Edward Lionheart and my ma, Diana Rigg, as his daughter. It tells the story of a grand ham actor entrapping London's leading theatre critics and murdering them one by one. And the critics (their modern-day equivalents) are out there now: an army of them poised with leaded spears. Sitting at my dressing table, I've come over all peculiar. A kamikaze vibe fills the air.

With abundant illusions and two live poodles, the play has all manner of potential technical potholes. The poodle pie in which Bette Bourne (as Michael Merridew) is force-fed his precious "doggy woggies" nearly didn't happen at all last night, after the dog called Larry (I kid you not) decided it preferred Bette to its handler. It galloped back on stage, skittering like a darting dustball, as grown men pounced upon it in vain. The dogs are

more expensive to employ than any of us. They even get their own dressing room.

I join the cast backstage. Bette sits with a poodle under each arm. Sally Dexter looks ravishing in blonde wig, 40-inch bust and six-inch heels. And heavenly Tim McMullan, playing the bibulous critic from the Daily Mail, has alco dots painted heavily in red across his nose and cheeks. We are a company of camp. Theatre of Blood is about the theatre - it is not a great philosophical masterpiece, nor is it intended as such. It's about plays and players, critics and criticism. It's a fun, frolicking feast: a spectacle, and a spectacular one at that.

Behind the swags I spy the chorus of tramps, loaded with pocketfuls of blood and bottles of meths - sorry, Ribena. There are blood bags aplenty backstage, tightly packed in Tupperware boxes. My own demise in the final scene is signified by my squirting a bag at my stomach, before turning to the audience to reveal that I have been stabbed. Last night the bloody thing didn't burst, so I looked down to examine it and got the full force of the explosion right in my face. I appeared to have been stabbed in the nose.

The tension in the wings causes one member of our company to fart. I get hopeless giggles. The toupee tape holding my false moustache in place (I play a girl in disguise rather than a man in drag) comes unstuck if I so much as smile. Now there's something else dangling from my visage to keep the eyelashes company. "Has anyone got any glue? HELLOOO." Here comes Jim Broadbent in full greasepaint. Our leading man, our star. And he is that, in every sense of the word.

The reviews are out. I always read reviews. I have a weakness for a good wordsmith, but sadly they are few and far between. Sometimes the crits are helpful - theirs can be the first objective opinion of a play. Other times they are pointlessly personal: "Mr Gielgud has the most meaningless legs imaginable." Or just plain vitriolic (see Nicholas de Jongh, would that he were as witty as Tynan). Our play has proved a critical curate's egg. Some rave, others rage. Given the murderous plot, we suspected as much.

Rachael Stirling is Miranda Lionheart in Theatre of Blood at the NT, London SE1 (020 7452 3000) until 27 August